Canister module

ABSTRACT

A canister module includes a canister housing in which a plurality of cylindrical adsorbent chambers filled with adsorbent are provided side by side with a gap therebetween. Canister-peripheral parts are connected to the adsorbent chambers through communicating openings provided on the canister housing and are in the gap.

This application is a 371 of PCT Application No. PCT/JP00/08327, filedNov. 27, 2000.

TECHNICAL FIELD

The present invention relates to a canister module for treating fuelvapor generated from a fuel tank with adsorbent such as activated carbonor the like.

BACKGROUND OF THE INVENTION

As an apparatus for treating vapor generated from a fuel tank of avehicle, there has conventionally been known a canister apparatus inwhich a recess portion (i.e., a gap) is provided between a pair ofadsorbent chambers so as to extend to substantially the entire height ofthe adsorbent chambers so that heat of adsorption generated in each ofthe adsorbent chambers can be released also into the recess portion,thereby inhibiting temperature rise of adsorbent to prevent itsadsorbing property from being degraded (see for example Japanese UtilityModel Publication No. H6-27818).

One adsorbent chamber of the canister apparatus is provided with atank-communicating opening, which communicates with the fuel tank, andwith a purge port-communicating opening, which communicates with a fuelconsumption system. The other adsorbent chamber is provided with anatmosphere-communicating opening. In addition, many kinds of peripheralparts are connected to the above-mentioned openings so as to controlcirculation and pressure of vapor. For example, a pressure control valveor the like for controlling the internal pressure of the fuel tank isconnected to the tank-communicating opening. A filter apparatus or thelike for removing dust in the air, which is to be introduced into theadsorbent chambers, is connected to the atmosphere-communicatingopening. These components, which are composed as separate parts from thecanister apparatus, are mounted fixedly in the vicinity of a housing ofthe canister apparatus by means of supporting members such as stays orthe like. There is a case where some of peripheral parts are received ina separate vessel from the housing of the canister apparatus to providea unit and such a unit is secured in the vicinity of the canisterapparatus.

However, in the conventional setting structure of the peripheral parts,the parts are required to be independently secured on the wall or thelike of an engine room, leading not only to increase in the number ofthe parts, but also to time consuming operations, thus increasing acost. Even when the peripheral parts are composed as a unit withutilization of a plastic housing, the number of the parts inevitablyincreases due to addition of the plastic housing.

When the recess portion is provided between the adsorbent chambers ofthe canister apparatus, the width of the canister apparatus increases,leading to increase in space required for installation of the canisterapparatus. In such a circumstance, arrangement of the many kinds ofperipheral parts around the canister apparatus occupies a considerablespace of the engine room due to such devices and parts, exertingpossibly an influence on arrangement of the other parts.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a canister module inwhich a canister housing, peripheral parts and the like relevant to acanister are put together into a compact body, thus making it possibleto decrease not only a space required to mount these parts on a vehicle,but also the number of the parts.

In order to attain the aforementioned object, a canister module of thepresent invention comprises: a canister housing in which a plurality ofadsorbent chambers filled with adsorbent are provided side by side sothat a gap is formed between opposite side walls for defining theadsorbent chambers, different parts from interior parts received in saidcanister housing are received in said gap.

According to such a structure, it is possible to effectively releaseheat of adsorption generated in the adsorbent chambers outside thechambers in the same manner as the conventional apparatus, because ofthe gap provided between the opposite side walls, which define theadsorbent chambers. Moreover, the different parts from the interiorparts, which are received in the canister housing, are received in thegap provided between the adsorbent chambers so that the gap can beutilized effectively as a receiving space for the parts, in addition toradiation purpose of heat. Accordingly, the canister housing and thedifferent parts can be put together into a single module, thus making itpossible to decrease a space required to mount them. Such a compact unitstructure causes the support member or the like to be commonly used tomount the different parts or to be omitted, leading to the decreasednumber of the parts and permitting reduction in cost.

In the canister module of the present invention, canister-peripheralparts serving as the different parts, which are connected to theadsorbent chambers through communicating openings provided on thecanister housing, may be received in the above-mentioned gap. Accordingto such a structure, it is possible to mount detachably the canisterhousing and the peripheral parts, which are to be connected to thecommunicating openings of the canister housing, on a vehicle in anassembled state. It is therefore possible to carry out easily a mountingoperation or a removing operation on the vehicle in comparison with acase where connecting operations for communicating openings andperipheral parts are carried out after they are mounted on a vehicle.

The canister module of the present invention may further comprise asupport member, which is detachable relative to the canister housing,and the canister-peripheral parts may be secured on the support member.In addition, the other canister-peripheral parts may be secured on thesupport member. Any parts other than the canister-peripheral parts maybe secured on the support member. According to such a structure, it ispossible to secure a plurality of canister-peripheral parts and the likeon the single support member to provide a sub-assembly. Such asub-assembly can be mounted on the canister housing so that many kindsof parts can easily be incorporated into the gap of the housing.

At least part of the support member may be put into the above-mentionedgap, and the canister-peripheral parts may be secured on the part, whichis put into the gap. According to such a structure, it is possible toreceive easily the canister-peripheral parts in the gap of the canisterhousing.

The part of the support member, which is put into the gap, may havevertical wall portions extending along the side walls of the adsorbentchambers and a cross portion for connecting the vertical wall portions.According to such a structure, it is possible to prevent the supportmember from improperly moving within the gap, permitting to holdsecurely the canister-peripheral parts.

In the present invention, it is possible to cause thecanister-peripheral parts received in the gap or the support member tofunction as a device for releasing heat of adsorption in the adsorbentchambers into the above-mentioned gap, by for example forming thecanister-peripheral parts and the support member of material having ahigh thermal conductivity or adopting a shape by which a high heatradiation effect can be provided.

The term “canister module” used in the present invention means an objectin which a canister apparatus composed of the canister housing andinternal parts received therein and the above-mentioned different partsare put together into a single module.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view illustrating an example of a canister module of anembodiment of the present invention;

FIG. 2 is a view illustrating a modification of the module as shown inFIG. 1;

FIG. 3 is a view illustrating an embodiment in which canister-peripheralparts are secured on the wall portion defining a recess portion;

FIG. 4 is a view illustrating an embodiment in which an additionalrecess is provided in a part of the recess portion to increase a surfacearea of the housing so that heat radiation property into the recessportion can be improved;

FIG. 5 is a view illustrating an embodiment in which a securingstructure for a canister filter is revised; and

FIG. 6 is a view illustrating an embodiment in which one of sideopenings of the recess portion is closed by means of a connecting wall.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 illustrates a: canister module of an embodiment of the presentinvention. The canister module 1 has a canister housing 2 formed ofplastic. The canister housing 2, which is typically a formed body ofplastic, is composed of a case body 3 and a lower cover 4 for closingthe lower opening of the base body 3. The case body 3 has a pair ofcylindrical portions 5, 6. The inside of each of the cylindricalportions 5, 6 is utilized as an adsorbent chamber, which is filled withadsorbent. Activated carbon is typically used as the adsorbent, althoughit is natural that the present invention is not limited only to this. Aconnecting portion 7 is provided at the lower ends of the cylindricalportions 5, 6. The adsorbent chambers in the inside of the cylindricalportions 5, 6 communicate with each other through the interior space ofthe connecting portion 7 so as to permit circulation of air and fuelvapor between the both chambers.

The upper ends of the cylindrical portions 5, 6 are closed by means ofupper covers 8, 9, respectively. The upper cover 8 is provided with atank-communicating opening 8 a and a purge port-communicating opening 8b. The upper cover 9 is provided with an atmosphere-communicatingopening 9 a. The upper covers 8, 9 may be manufactured in a separateprocess from that for the cylindrical portions 5, 6 and then assembled,or may be integrally formed with the cylindrical portions 5, 6. Theupper cover 8 may be provided in its inside with a liquid collector forstoring liquid component of fuel, which flows from thetank-communicating opening 8 a.

A recess portion (i.e., a gap) 10 is provided between the opposite sidewalls 5 a, 6 a of the cylindrical portions 5, 6 so as to extend from theupper ends of the cylindrical portions 5, 6 toward the connectingportion 7. The recess portion 10 opens upward at its upper end of thecanister housing 2 as well as in the transverse direction (i.e., thedirection perpendicular to a plane of the paper of the figure) at theopposite side ends. The recess portion 10 receives an U-shaped bracket11. The bracket 11 is provided at the upper ends with flanges 11 a, 11a, which project from the recess portion 10. These flanges 11 a, 11 aare fixed on the upper covers 8, 9 by means of attaching screws 12, 12,respectively so that the bracket 11 is suspended within the recessportion 10.

Some canister-peripheral parts are secured on the bracket 11. In theexample as shown in FIG. 1, a bypass solenoid valve 15 and a two-wayvalve 16 are fixed on one vertical wall portion 11 b of the bracket 11with the use of a base plate 20 and attaching screws 21. Abent-shut-solenoid valve 17 is fixed on the other vertical wall port on11 c with the use of a base plate 22 and an attaching screw 23. Acanister filter 18 is fixed on the bottom wall portion 11 d with the useof a base plate 24 and an attaching screw 25.

The bypass solenoid valve 15, which is connected to a fuel tank (notshown), can open or close a fluid passage for introducing fuel vaporfrom the fuel tank into the canister housing 2. The two-way valve 16 isused to maintain the internal pressure of the fuel tank within anappropriate range. The two-way valve 16 has an internal passage. The oneend of the internal passage is connected to the bypass solenoid valve 15and the other end thereof is connected to the tank-communicating opening8 a through a tube 19. The bent-shut-solenoid valve 17, which isconnected to the atmosphere-communicating opening 9 a through a tube 26,can open or close a communicating passage for air between the inside andoutside of the canister housing 2 through the atmosphere-communicatingopening 9 a. The canister filter 18 is used to filter air, which isintroduced from the atmosphere-communicating opening 9 a into thehousing 2, during a purge treatment (i.e., a treatment for causing anegative pressure to be generated in the purge port-communicatingopening 8 b so as to introduce air from the atmosphere-communicatingopening 9 a into the housing 2, thereby removing fuel constituentadsorbed by adsorbent). The canister filter 18 has an internal passage.The end of the internal passage is connected to the bent-shut-solenoidvalve 17 through a tube 27 and the other end thereof communicates withthe air (not shown). In addition, the upper cover 8 is provided with apressure sensor 28 for detecting pressure of fuel vapor supplied fromthe fuel tank.

According to the above-described structure, the recess portion 10 formedas the gap between the adsorbent chambers can be utilized as a space forreceiving the parts 15 to 18 so that the canister apparatus and theperipheral parts can be put together into a module serving as a singleunited body. It is therefore possible to decrease a space required forinstallation of them on a vehicle. There is no need to provideindividually support members such as brackets for the parts 15 to 18,thus decreasing the number of the parts. These parts 15 to 18 are fixedon the common bracket 11. As a result, it is possible to fix these parts15 to 18 on the bracket 11 and carry out a connecting operation forthese parts prior to the fixing of the bracket 11 to the housing 2 sothat these peripheral parts can be assembled into a so-calledsub-assembly. Then, the placement of the bracket 11 in the recessportion 10 and the fixation of it on the housing 2 will suffice. It istherefore possible to carry out easily not only a fixing operation ofthe parts, but also a maintenance and exchange operation. The bracket 11may be formed of material having a high thermal conductivity or may havea shape by which a high heat radiation effect can be provided, thusimproving heat radiation property from the adsorbent chambers into therecess portion 10.

The present invention, which is not limited only to the above-describedembodiment, may be carried out in the form of the other embodiments. Forexample, the recess portion 10 may be completely closed by means of abracket 30 as shown in FIG. 2, thus improving a rust prevention propertyand the like of the peripheral parts. In this case, arrangements arepreferably made so as to effectively radiate heat, which is transferredfrom the adsorbent chambers to the recess portion, outside the bracket30.

FIGS. 3 to 6 illustrate the other embodiment of the present invention.The same reference numerals are given to components in these figures,which are common in the other figures. In the embodiment as shown inFIG. 3, the bracket 11 as shown in FIG. 1 is omitted. A bypass solenoidvalve 15 and a two-way valve 16 are fixed on the side wall 5 a of thecylindrical portion 5 with the use of a base plate 20 and attachingscrews 21. A bent-shut-solenoid valve 17 is fixed on the side wall 6 aof the cylindrical portion 6 with the use of a base plate 22 and anattaching screw 23. A canister filter 18 is fixed on the upper wall 7 aof the connecting portion 7 with the use of a base plate 24 and anattaching screw 25. Also in such an embodiment, the base plates 20, 22and 24 serving as support members may be formed of material having ahigh thermal conductivity or may have a shape by which a high heatradiation effect can be provided, thus improving heat radiation propertyfrom the adsorbent chambers into the recess portion 10.

In the embodiment as shown in FIG. 4, one cylindrical portion 5 isprovided at its upper portion with a recess portion 5 b in which abypass solenoid valve 15 and a two-way valve 16 are fixed with the useof a base plate 20 and attaching screws 21. The other parts 17, 18 arein the same fixing condition as those in FIG. 3. In this embodiment,provision of the recess portion 5 b causes the surface area of thehousing to increase, thus facilitating heat radiation into the recessportion 10.

In the embodiment as shown in FIG. 5, a bypass solenoid valve 15 and atwo-way valve 16 are fixed on the side wall 5 a of the cylindricalportion 5 with the use of a base plate 20 and attaching screws 21. Acanister filter 18 is fixed on the side wall 6 a of a cylindricalportion 6 so as to come into contact with the side wall 6 a and extendto substantially the entire height thereof. In addition, a purgesolenoid valve 33 is fixed on the side wall 18 a of the canister filter18 with the use of a base plate 34 and attaching screws 35, 35. Thepurge solenoid valve 33, which is connected to the purge-portcommunicating opening 8 b through a tube 36, can open or close a passageconnecting the purge-port communicating opening 8 b to a purge port (notshown). In such an embodiment, the housing of the canister filter may beformed of material having a high thermal conductivity or may have ashape by which a high heat radiation effect can be provided, thusimproving heat radiation property from the adsorbent chambers into therecess portion 10.

Parts received in the recess portion 10 are not limited only to those inthe above-described embodiments and the other parts may be received inthe recess portion 10. Some of auxiliary parts for mounting the canisterhousing 2 in the engine room may for example be received in the recessportion 10. Some of parts (for example, a casing or housing) to bereceived in the recess portion 110 may be integrally formed with thecanister housing 2 in the same forming process. The recess portion 10may be provided with a heat-exchanging element such as fins or the likefor facilitating heat radiation from the adsorbent chambers. Heatcapacity of the bracket 11 and the base plates 20, 22 and 24 may beincreased by increasing for example the thickness of them, so as toutilize the support members as a heat sink. Heat capacity of theperipheral parts such as a canister filter 18 may be increase so as toutilize the peripheral parts as the heat sink.

The recess portion 10 is not limited only to the shape as shown in FIG.1. The recess portion 10 may be closed by means of a connection wall 40,which connects the cylindrical portions 5 a and 6 a to each other, asshown in FIG. 6.

According to the present invention as described in detail, the canisterhousing and the different parts can be put together into a singlemodule, thus making it possible to decrease a space required to mountthem. Such a compact unit structure causes the support member or thelike to be commonly used to mount the different parts or to be omitted,leading to the decreased number of the parts and permitting reduction incost.

What is claimed is:
 1. A canister module comprising: two cylindricalhousings that each contain a chamber with an adsorbent, said housingshaving generally parallel longitudinal axes and being spaced from eachother with a floor therebetween so that sidewalls of said chambers andsaid floor define a passageway between said two housings, saidpassageway extending in opposite directions perpendicular to a planecontaining said longitudinal axes and in a direction away from saidfloor; and components for operating said module attached within saidpassageway to at least one of said sidewalls and said floor so as toleave a heat radiation space within said passageway between saidcomponents.
 2. The canister module of claim 1, wherein one of saidchambers is connected to outside air through a filter and another ofsaid chambers is connected to a vapor source through a valve, andwherein said components comprise said filter and said valve.
 3. Thecanister module of claim 2, further comprising a second valve betweensaid filter and said one of said chambers, said second valve beingwithin said passageway.
 4. The canister module of claim 2, wherein eachof said housings further comprises a vapor opening in an end thereofopposite said floor, and further comprising a first hose that leads fromsaid filter within said passageway to one said vapor opening and asecond hose that leads from another said vapor opening to said valvewithin said passageway.
 5. The canister module of claim 1, furthercomprising a generally U-shaped mounting bracket within said passagewayand attached outside said passageway to ends of said housings oppositesaid floor.
 6. The canister module of claim 5, wherein one of saidchambers is connected to outside air through a filter and another ofsaid chambers is connected to a vapor source through a valve, andwherein said components comprise said filter and said valve which arewithin said passageway and attached to said bracket so as to leave theheat radiation space in said passageway.
 7. The canister module of claim1, further comprising plural mounting brackets within said passagewayand attached to at least one of said sidewalls and said floor.
 8. Thecanister module of claim 7, wherein one of said chambers is connected tooutside air through a filter and another of said chambers is connectedto a vapor source through a valve, and wherein said components comprisesaid filter and said valve which are within said passageway and attachedto a respective one of said mounting brackets so as to leave the heatradiation space in said passageway.
 9. The canister module of claim 1,further comprising a cover for closing the passageway in the oppositedirections perpendicular to the plane containing said longitudinal axesand in the direction away from said floor.
 10. A canister modulecomprising: two cylindrical housings that each contain a chamber with anadsorbent, said housings having generally parallel longitudinal axes andbeing spaced from each other with a floor therebetween so that sidewallsof said chambers and said floor define a gap between said two housings,said chambers of said two housings being in vapor communication witheach other through a path in said floor; one of said chambers beingconnected to outside air through a filter and another of said chambersbeing connected to a vapor source through a valve; and a generallyU-shaped mounting bracket within said gap and attached outside said gapto ends of said housings opposite said floor, each of said filter andsaid valve being within said gap and attached to said bracket so as toleave a heat radiation space in said gap.
 11. The canister module ofclaim 10, further comprising a second valve between said filter and saidone of said chambers, said second valve being within said gap andattached to said bracket.
 12. The canister module of claim 10, whereineach of said housings further comprises a vapor passage in the endthereof opposite said floor, and further comprising a first hose thatleads from said filter within said gap to one said vapor passage and asecond hose that leads from another said vapor passage to said valvewithin said gap.
 13. The canister module of claim 10, wherein saidbracket is spaced from said floor so as to provide a heat radiationspace.
 14. The canister module of claim 10, further comprising a coverfor closing said gap in the opposite directions perpendicular to theplane containing said longitudinal axes and in the direction away fromsaid floor.
 15. A canister module comprising: two cylindrical housingsthat each contain a chamber with an adsorbent, said housings havinggenerally parallel longitudinal axes and being spaced from each otherwith a floor therebetween so that sidewalls of said chambers and saidfloor define a gap between said two housings, said chambers of said twohousings being in vapor communication with each other through a path insaid floor; one of said chambers being connected to outside air througha filter and another of said chambers being connected to a vapor sourcethrough a valve; and plural mounting brackets within said gap andattached to at least one of said sidewalls and said floor, each of saidfilter and said valve being within said gap and attached to a respectiveone of said brackets so as to leave a heat radiation space in said gap.16. The canister module of claim 15, further comprising a second valvebetween said filter and said one of said chambers, said second valvebeing within said gap and attached to one of said brackets.
 17. Thecanister module of claim 15, wherein each of said housings furthercomprises a vapor passage in the end thereof opposite said floor, andfurther comprising a first hose that leads from said filter within saidgap to one said vapor passage and a second hose that leads from anothersaid vapor passage to said valve within said gap.